Monday 15 March 2010 10.14 EDT
First published on Monday 15 March 2010 10.14 EDT

We had our first taste this morning of Dave, live and unplugged, on the election trail. There were boos and heckling when David Cameron appeared in shirtsleeves shortly before lunch to take unscripted questions from apprentices at Lewisham college at its Deptford campus in south-east London.

All went well initially as Cameron was heard in respectful silence by around 60 apprentices as he outlined his plans to tackle Britain's record £178bn fiscal deficit. There was the odd murmur as the Tory leader, surrounded by apprentices sitting on woodwork benches, dwelled for perhaps a little too long on his plans to exempt new businesses from paying taxes on their first 10 employees.

Then he threw the session open to questions. The first questioner pointedly asked Cameron whether he would take Britain out of recession. As Cameron warned that Britain would end up like Greece unless it tackled the fiscal deficit, the heckles started. "Yeah, but we need more money," one apprentice shouted out.

At this point Cameron almost lost the audience when one apprentice raised Margaret Thatcher's record and pointed out that unemployment had been far higher during recessions under the Tories. The apprentice was reading from the only script of the day, which bore a remarkable similarity to Labour's anti-Tory bullet points.

With the noise level rising Cameron turned round and took questions from the media a little earlier than usual. When he felt confident that the noise had died down, Cameron turned back to the apprentices, who asked him about the educational maintenance allowance and housing.

Some of the people in this room seem quite angry with you when they're talking about Margaret Thatcher. Is that a sign that you have failed to show the public that the Tories have changed?

This is Cameron's reply:

No. I don't think that's right. Look, politics should be lively, in the round. There should be arguments, there should be debates about what happened in the past.

At the point one of his questioners gave Cameron the thumbs up, prompting him to say:

Look, I got the thumbs up from the guy who said he didn't like Thatcher. That is what it should be. Find me the time when the prime minister stands in a crowded room without anyone pre-screened. This is what politics should be like. This is what you are going to get from me at this election: not a script, not a lectern, not surrounded by a bunch of hand-picked people. But proper, live public meetings where actually you can argue about the future of our country and then together we can decide. Right?

Perhaps Cameron has had his soapbox moment. John Major famously found found his feet during the 1992 general election campaign when he started answering unscripted questions through a megaphone as he stood on a soapbox.